The present invention relates generally to communications systems that service voice, data and multimedia communications and in particular to a method and apparatus for managing a personal mobility system that operates with a plurality of heterogeneous communication networks to route voice, data and multimedia communications to the user via one or more of a plurality of communication systems based on a personal identifier of the user. Still more particularly, the present invention relates to a method and apparatus for supporting nomadic computing of a personal mobility system with transparent virtual networking, information storage, and mobility when the user is traveling from one location to another and/or using different computer platforms or operating modes.
Voice communication systems are well known in the art. Examples of voice communication systems include the Public Switched Telephone Network (PSTN), cellular wireless communication systems, and other systems that are primarily intended to service voice traffic. Data communication systems are also well known in the art. Examples of data communication systems include the Internet, Local Area Networks (LANs), Wide Area Networks (WANs), and asynchronous transfer mode (ATM) networks, among others.
While voice communication systems are primarily intended to service voice traffic, they may also be adapted to service data traffic. Likewise, data communication systems, while primarily intended to service data traffic, may also be adapted to service voice traffic (e.g., Internet Protocol (IP) Telephone). In 1996, for the first time in history, the volume of data traffic on carrier backbone networks exceeded the volume of voice traffic. This historical event signaled the fundamental transformation from networks dominated by voice to networks dominated by data. Today, data traffic is growing 10 times faster than voice trafficxe2x80x94more than 30 percent growth per year for data traffic versus 3 percent growth per year for voice traffic.
However, as the availability of communications increases, the difficulty of operating the resultant communication systems increases. For example, a single user may access the Internet, a public switched telephone network (PSTN), a cellular network, and other networks in a single day. The single user may be at a desk for part of the day, at home for a portion of the day, on the road for a portion of the day, and at yet other locations during other parts of the day. Therefore, it can be very difficult to determine how to reach the user by voice and/or to send data communications to a single user. Because the single user may be accessing any of these dissimilar networks at any given time, it is difficult, if not impossible, to direct a communication to the single user. Most particularly, it is extremely difficult to determine the appropriate number to dial or address to employ in the case where an immediate conversation (i.e., voice communication) is required.
In addition to the above mentioned mobility problems, now surfacing is the problem of personal computing mobility from mobile stations. The Internet""s World Wide Web (WWW) interface has totally revolutionized the way information is accessed in all sectors of the economy. The availability of global services allows users to travel almost anywhere and still have access to the Internet. However, the system architecture needed to support nomads as they travel from one location to another is not yet in place.
Nomadicity is the term used to define the transparent, integrated and convenient form of system support needed to provide a rich set of computing and communications capabilities and services to nomads as they move from place to place. Nomadicity is a new paradigm in the use of computer and communications technology. The emergence of portable devices featuring high performance, low power requirements and compact size is changing the way we think about information processing. Access to computing and communications is now required not only within the office environment, but also during transit to/from various other locations. Nomadicity offers huge potential for improved capability and user convenience, yet it also presents a huge problem for interoperability.
Nomadic computing is a newly emerging technology. Among the solutions being proposed, mobile IP is the most prominent. Mobile IP is an extension of IP that allows mobile nodes to roam transparently from place to place within the Internet. Mobile IP affects the routing of datagrams within the Internet by effectively allowing the home agent to create a tunnel, using encapsulation, between the mobile node""s home IP address associated with its home network and whatever care-of address identifies its current point of attachment.
The ability provided by mobile IP to deliver packets to a mobile computer or some other mobile station does not completely solve the problem of nomadic computing. Some of the key requirements imposed by nomadic computing include: enabling interoperation among many kinds of infrastructures; dealing with the unpredictability of user behavior, network capability and computing platforms; and delivering maximum independence between the network and the application. The emerging trend toward nomadicity is characterized by multimedia, networking and portability.
Likewise, there is a need in the art for a system and method of operation that employ multiple heterogeneous networks to effectively route communications among nomadic users.
Further, there is a need in the art for a system and method for supporting nomadic computing without upgrading or replacing system routers presently in use.
To overcome the shortcomings of the prior systems, among other shortcomings, the present invention provides a method and apparatus for nomadic computing by means of transparent virtual networking, information storage, and mobility when the user is traveling from one location to another and/or using different computer platforms or operating modes. Personal mobility domain name service (PMDNS) is originally designed to provide personal mobility via a personal identifier. Because of generic system architecture which uses the Internet as backbone, interoperating with existing access networks, it is also wise to provide nomadic computing services.
To accomplish such operations, a personal mobility directory server is updated with information concerning a user""s nomadicity. When the user travels from one place to another, the user registers with a PMDNS server at an IP port for computing communications. The PMDNS employs the user""s terminal personalization together with a usage profile and session characteristics to map a party""s identifier to a terminal""s identifier. The IP address of the user""s current location can be used in concert with the terminal""s identifier, which is in itself an IP address, to route incoming computing communications connection requests to the current location of the user. This information is returned by the PMDNS directory server to the access network for the setup of the communications.
In the present invention, a PMDNS operates in an environment with the Internet as backbone, cooperating with existing access networks, such as a PSTN or cellular network and doe not require the modification or replacement of existing routers. Therefore, the present invention enables nomadic computing in concert with other media. Also, the present invention is accomplished by means of an application protocol, PMDNS, rather than a network protocol that would not affect much of the existing protocol stack.
The present invention provides a means for dealing with the unpredictability of user behavior and changes in computing platform by association with terminal personalization provided in the PMDNS, while still allowing for cross-network nomadic computing. Finally, the present invention utilizes a PMDNS which applies session characteristics stored in a database as an input parameter to determine and return the TID(s) of the terminal(s) appropriate for the given session characteristics. This enables voice, data and/or multimedia services to be simultaneously matched to an incoming session.